As indicated in Caronna et al., Tetrahedron Letters, No. 7, pp. 657-660 (1979), U.S. Pat. No. 4,172,151 (Moore), and German Offenlegungsscrift 2,336,551 (Sandoz), unsymmetrically substituted biphenyls are useful as pharmaceuticals, agricultural chemicals, antioxidants, specialty chemicals, and intermediates therefor; and they can be prepared by a variety of techniques.
Wright et al., Journal of Organic Chemistry, Vol. 33, No. 3, 1968, pp. 1245-1246, teach that one such unsymmetrically substituted biphenyl, i.e., 2,6-di-t-butyl-4-(p-nitrophenyl)phenol, can be prepared by reacting 2,6-di-t-butylphenol with p-chloronitrobenzene in an inert solvent and in the presence of a strong base. However, it has been found that no reaction occurs when m-chloronitrobenzene is substituted for p-chloronitrobenzene in such a reaction.
Kornblum et al., Journal of Organic Chemistry, Vol. 41, No. 9, 1976, pp. 1560-1564, teach that various nucleophiles are capable of displacing a nitro group of certain substituted nitrobenzenes in a dipolar aprotic solvent, such as hexamethylphosphoramide. 1,2-, 1,3-, and 1,4-Dinitrobenzenes and 4-nitrophenyl phenyl sulfone are exemplary of the substituted nitrobenzenes they employed; and their nucleophiles included, e.g., sodium benzenesulfinate, sodium thiophenoxide, sodium methoxide, sodium methyl mercaptide, etc.